In the Bellcore GR-2892-CORE and GR-1298-CORE specifications, advanced intelligent network (AIN) toll free service based on a 3 or 6 digit trigger must be able to take precedence over conventional 3-digit Bellcore TR-NWT-000533 based intelligent network (IN) toll free service. However, in the GR-1298-CORE specification IN toll-free service checking must occur earlier in the call model than the check for AIN toll free service. As a result, if a numbering plan area code of a called number is subject to IN toll free service, the IN toll free service would be invoked before a more specific 6-digit AIN trigger is encountered. Thus, AIN and IN toll free services cannot simultaneously be offered at the same service switching point. The arrangement of existing programming to provide AIN and IN services is such that rearrangement of processing steps in either of the call models would remove the call models from compliance with the Bellcore specifications, affecting many other call processing functions and features. Therefore, it would be desirable to simultaneously offer call processing based on the AIN call model and the IN call model without departing from the Bellcore specifications as this would facilitate user transition from the Bellcore TR-NWT-000533 specification to the Bellcore GR-2892-CORE and GR-1298-CORE specifications in a manner transparent to users.